1. Field of Invention
The present invention relates to a method for controlling a semiconductor manufacturing process. More particularly, the present invention relates to a method for controlling a polishing process.
2. Description of Related Art
The chemical mechanical polishing process is widely applied on the method for forming a structure, such as dual damascene, a metal plug and a top electrode of the trench capacitor, and on the planarization of the dielectric layer and becomes an indispensable process for manufacturing the integrated circuit.
In the chemical mechanical polishing process, the major process parameters include the pressure value applied on the polishing head, the composition of the slurry and the polishing particles, the material of the polishing pad, the relative linear rate between the wafer and the polishing pad and the temperature. However, the polishing result of the chemical mechanical polishing process is also affected by the factors other than the process parameters. Hence, the yield and the reliability of the polishing process are affected.
Taking the dual damascene process as an example, the copper film formed by using the electroplating process possesses relatively large thickness around the edge of the wafer. Accordingly, after the chemical mechanical polishing process is performed, the problems of copper remaining on the wafer edge and over polishing and dishing around the center of the wafer happen. Hence, the electrical properties of the dual damascene structures are not even over the entire wafer.